Gtk-Gnutella is a full-featured Gnutella client using GTK+. It contains all widely deployed Gnutella features, including DHT support. It is extremely efficient, using little CPU time and memory. It is meant to be left running 24x7. It is fully compatible with UPnP and NAT-PMP, and as such is easy to use behind a firewall supporting one of these port mapping technologies.

VICE is a Versatile Commodore Emulator, i.e. a
program that runs on a Unix, Win32, MS-DOS, Mac OS X, Amiga, or RiscOS machine and executes programs intended for the old 8-bit Commodore computers.
The current version emulates the C64, C128, VIC20, Plus4, C64-DTV, all the PETmodels, and the CBM-II (aka C610).

libvm68k is an M68000 virtual machine library written in C++. It was first developed for use in Virtual X68000 but only contains the generic layer of it so that it can be reused in other emulator projects.

Eukleides is a computer language devoted to elementary plane geometry. It aims to be a fairly comprehensive system to create geometric figures, either static or dynamic. It can handle geometric types of data like points, vectors, lines, circles, or conics. A Eukleides script usually consists of a declarative part where objects are defined and a descriptive part where objects are drawn. Nonetheless, Eukleides is also a full featured programming language, providing conditional and iterative structures, user defined functions, modules, etc. The Eukleides distribution provides two distinct interpreters: "eukleides" and "euktopst". The former interpreter produces Encapsulated PostScript (EPS). The latter produces PSTricks macros, allowing Eukleides to be used with LaTeX.

Jackbeat is a multi-platform audio sequencer for musicians and sound artists. Featuring a drum machine interface with animations for easy and playful editing, it is built for both composition and live setups with high interactivity needs. It is extremely easy to use yet powerful via connecting with other applications and plugins using JACK and OSC. Jackbeat loads and saves .jab files, Jackbeat's xml+tar open file format, and supports CoreAudio, ASIO, ALSA, PulseAudio, and JACK.

cclite is a lightweight implementation of a community currency registry for local exchange trading systems (LETS) and other alternative money systems. It uses multi-registry, multi-currency, Web-services-based (SOAP) transactions, and is templated to give multi-lingual properties. As of 2009, it has an SMS interface and versions for Debian, cpanel-based, Fedora and Windows XP. As of 2012 it has decimal currencies, templates for many languages, and a REST-style interface for integration with CMS and social networking software.

Grapple is designed to be a simple network layer,
allowing the addition of multiuser features to an
application for as little as a dozen lines of
code. However, it also allows for more. It
features simple client-server networking that
keeps all clients aware of all other clients,
passworded servers, and data transfer via TCP,
UDP, or reliable UDP. Advanced features include
network messaging via push, pull, or a
combination, multiple methods of querying users,
user groups for client bandwidth saving, network
load reacting data transmission and
retransmission, background pinging to monitor
network states, server failover, and a fully
functional lobby system.

Xournal is a GTK+ application for
notetaking, sketching, and keeping a journal using
a stylus on Tablet PCs and other platforms. It
aims to provide superior graphical quality
(subpixel resolution) and overall functionality.

QP is a family of lightweight software frameworks for building responsive and modular real-time embedded applications as systems of cooperating, event-driven active objects (actors). The QP family consists of QP/C, QP/C++, and QP-nano frameworks, which are all strictly quality controlled, superbly documented, and commercially licensable. The behavior of active objects is specified in QP by means of hierarchical state machines (UML statecharts). The frameworks support manual coding of UML state machines in C or C++ as well as automatic code generation by means of the free QM modeling tool. All QP frameworks can run on bare-metal MCUs, completely replacing a traditional RTOS. Ports and ready-to-use examples are provided for all major CPUs, such as ARM Cortex-M, ARM7/9, MSP430, C28x, C55x, RX, R8C, AVR32, AVRMega, PIC24/dsPIC, as well as Arduino and mbed. QP/C and QP/C++ can also work with a traditional OS/RTOS, such as: POSIX (Linux, QNX), Windows, VxWorks, ThreadX, and uC/OS.